<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>argCall</title>
</head>
<body>

</body>
<script type="text/javascript">
function a(a, b, c, d) {
// 	alert(arguments.shift());  //undefined
	alert(Array.prototype.shift.call(arguments));
}
a(1, 2, 3, 4);
</script>
</html>